if X@Y=X+ (x + 1) + (x + 2) +... + (x + Y-1), where x and y are natural numbers, and 1@50 The value of

if X@Y=X+ (x + 1) + (x + 2) +... + (x + Y-1), where x and y are natural numbers, and 1@50 The value of

x=1,y=50,1@50=1+2+3+...+50=1/2 *(1+50)*50=1275